Fall_25_Abnormal_Presentation

Question 1

What defines multiple pregnancy?

Answer 1

Simultaneous development of more than one fetus in the uterus.

Question 2

What is the most common type of multiple pregnancy?

Answer 2

Twin gestation.

Question 3

What is presentation in obstetrics?

Answer 3

The part of the fetus overlying the maternal pelvic inlet that will engage the birth canal.

Question 4

What is the only normal fetal presentation?

Answer 4

Cephalic presentation.

Question 5

What is an asynclitic presentation?

Answer 5

The fetal head is tilted toward one shoulder, causing one parietal eminence to enter the pelvis first.

Question 6

Define lie in obstetrics.

Answer 6

The relationship between the fetal long axis and maternal long axis.

Question 7

What is the normal fetal lie?

Answer 7

Longitudinal lie.

Question 8

Which lie usually requires cesarean delivery?

Answer 8

Transverse lie.

Question 9

What defines position?

Answer 9

Relationship of a specific fetal bony point (e.g., occiput, sacrum, mentum, acromion) to the maternal pelvis.

Question 10

What does attitude describe?

Answer 10

Relationship of fetal parts to one another—usually head to trunk (flexed, extended, or military).

Question 11

Define breech presentation.

Answer 11

Longitudinal lie where buttocks or lower extremities overlie the pelvic inlet.

Question 12

List the three varieties of breech presentation.

Answer 12

Frank (hips flexed, knees extended), Complete (hips and knees flexed), Incomplete (one or both legs extended at hips).

Question 13

Which type of breech has the highest risk of cord prolapse?

Answer 13

Incomplete breech.

Question 14

What is the most common abnormal presentation?

Answer 14

Breech presentation.

Question 15

What is the goal of external cephalic version (ECV)?

Answer 15

Convert breech or shoulder presentation to vertex.

Question 16

When is ECV optimally performed?

Answer 16

After 36–37 weeks’ gestation.

Question 17

What is the main contraindication for ECV?

Answer 17

Oligohydramnios (insufficient amniotic fluid).

Question 18

What factors increase ECV success?

Answer 18

Normal fluid, non-engaged presenting part, posterior fetal back, parous mother, frank/transverse breech.

Question 19

What can improve ECV success rate?

Answer 19

Neuraxial anesthesia or tocolytic administration.

Question 20

What factors influence the delivery route for breech presentation?

Answer 20

Provider experience, fetal status, and institutional protocols.

Question 21

What is the preferred mode for most breech deliveries today?

Answer 21

Cesarean section.

Question 22

What should be discussed before attempting vaginal breech delivery?

Answer 22

Higher risk of neonatal morbidity/mortality compared with cesarean.

Question 23

Define spontaneous breech delivery.

Answer 23

Fetus delivers without traction or manipulation other than support.

Question 24

Define assisted breech delivery.

Answer 24

Infant delivers spontaneously to umbilicus; OB assists chest and head.

Question 25

Define total breech extraction.

Answer 25

Entire fetus delivered by traction on feet; typically used for second twin only.

Question 26

Why should breech deliveries occur in an OR?

Answer 26

Risk for emergency cesarean and need for immediate anesthesia.

Question 27

Describe face presentation.

Answer 27

Neck hyperextended; face is presenting part; vaginal delivery possible in ~70–80% of cases.

Question 28

Describe brow presentation.

Answer 28

Neck partially extended; usually requires cesarean due to dystocia.

Question 29

Define compound presentation.

Answer 29

Extremity presents alongside main part (often arm + head).

Question 30

What is the key risk in compound presentation?

Answer 30

Umbilical cord prolapse and nerve injury to presenting limb.

Question 31

What is shoulder presentation and how is it managed?

Answer 31

Transverse lie; requires cesarean unless ECV or internal podalic version for second twin.

Question 32

Define monozygotic twins.

Answer 32

One fertilized egg splits; genetically identical; always same sex.

Question 33

Define dizygotic twins.

Answer 33

Two separate ova fertilized by different sperm; genetically distinct; often different sexes.

Question 34

What determines chorionicity?

Answer 34

Timing of zygotic division in monozygotic twins or independent fertilization in dizygotic twins.

Question 35

How is chorionicity best determined?

Answer 35

Ultrasound in the first or early second trimester.

Question 36

Why is chorionicity clinically important?

Answer 36

Determines risk of vascular anastomoses → twin-to-twin transfusion syndrome (TTTS).

Question 37

How does multiple gestation affect cardiovascular physiology?

Answer 37

↑ CO (20%), ↑ SV (15%), ↑ HR (~3.5%).

Question 38

How does lung physiology change in multiple gestation?

Answer 38

↓ total lung capacity and ↓ FRC due to uterine enlargement.

Question 39

How does blood volume differ in twin pregnancy?

Answer 39

Plasma volume increases by an additional 750 mL.

Question 40

How much greater is average blood loss at delivery in multiples?

Answer 40

~500 mL more than singleton deliveries.

Question 41

Name a key fetal complication unique to multiple gestation.

Answer 41

Twin-to-twin transfusion syndrome.

Question 42

What is the main cause of increased maternal morbidity in multiple gestations?

Answer 42

Higher incidence of preeclampsia, preterm labor, and hemorrhage.

Question 43

What is ACOG’s statement regarding multiple gestations and hospitalization risk?

Answer 43

Women with multiples are ~6× more likely to be hospitalized with complications.

Question 44

Optimal delivery timing for twins and triplets?

Answer 44

Twins – 38 weeks; Triplets – 35 weeks.

Question 45

Does twin gestation contraindicate vaginal delivery?

Answer 45

No, but cesarean incidence is higher.

Question 46

What is the preferred labor analgesia for twins?

Answer 46

Epidural — allows conversion to surgical anesthesia if needed.

Question 47

Why should epidural catheter function be confirmed early?

Answer 47

Inadequate block may require urgent replacement before emergent delivery.

Question 48

Why is large-bore IV access important in multiple gestations?

Answer 48

Increased risk of hemorrhage and need for rapid fluid/blood administration.

Question 49

Why is preoxygenation crucial before GA in multiple gestations?

Answer 49

Higher O₂ consumption and ↓ FRC increase risk for hypoxemia during apnea.

Question 50

What must always be available during multiple deliveries?

Answer 50

A clinician skilled in neonatal resuscitation.